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Categories: Ecology: General, Space: Astronomy
Published Hubble follows shadow play around planet-forming disk
(via sciencedaily.com) Original source The young star TW Hydrae is playing 'shadow puppets' with scientists observing it with NASA's Hubble Space Telescope. In 2017, astronomers reported discovering a shadow sweeping across the face of a vast pancake-shaped gas-and-dust disk surrounding the red dwarf star. The shadow isn't from a planet, but from an inner disk slightly inclined relative to the much larger outer disk -- causing it to cast a shadow. One explanation is that an unseen planet's gravity is pulling dust and gas into the planet's inclined orbit. The young star TW Hydrae is playing 'shadow puppets' with scientists observing it with NASA's Hubble Space Telescope. Now, a second shadow -- playing a game of peek-a-boo -- has emerged in just a few years between observations stored in Hubble's MAST archive. This could be from yet another disk nestled inside the system. The two disks are likely evidence of a pair of planets under construction.
Published Vanishing glaciers threaten alpine biodiversity
(via sciencedaily.com) Original source With glaciers melting at unprecedented rates due to climate change, invertebrates that live in the cold meltwater rivers of the European Alps will face widespread habitat loss, warn researchers. Many of the species are likely to become restricted to cold habitats that will only persist higher in the mountains, and these areas are also likely to see pressures from the skiing and tourism industries or from the development of hydroelectric plants.
Published Astronomers spot a star swallowing a planet
(via sciencedaily.com) Original source Scientists have observed a star swallowing a planet for the first time. Earth will meet a similar fate in 5 billion years.
Published Indo-Pacific corals more resilient to climate change than Atlantic corals
(via sciencedaily.com) Original source In the face of global warming and other environmental changes, corals in the Atlantic Ocean have declined precipitously in recent years, while corals in the Pacific and Indian Oceans are faring better. By describing several species of symbiotic algae that these corals need to grow, an international team has found that these mutualistic relationships from the Indo-Pacific may be more flexible and ultimately resilient to higher ocean temperatures than those in the Atlantic.
Published Astronomers find distant gas clouds with leftovers of the first stars
(via sciencedaily.com) Original source Using ESO's Very Large Telescope (VLT), researchers have found for the first time the fingerprints left by the explosion of the first stars in the Universe. They detected three distant gas clouds whose chemical composition matches what we expect from the first stellar explosions. These findings bring us one step closer to understanding the nature of the first stars that formed after the Big Bang.
Published Fossil find in California shakes up the natural history of cycad plants
(via sciencedaily.com) Original source According to researchers, a new analysis of an 80-million-year-old permineralized pollen cone found in the Campanian Holz Shale formation located in Silverado Canyon, California, offers a more accurate cycad natural history -- one where the plants diversified during the Cretaceous.
Published Webb finds water vapor, but from a rocky planet or its star?
(via sciencedaily.com) Original source Astronomers used NASA's James Webb Space Telescope to study a rocky exoplanet known as GJ 486 b. It is too close to its star to be within the habitable zone, with a surface temperature of about 800 degrees Fahrenheit (430 degrees Celsius). And yet, their observations show hints of water vapor.
Published Astronomers detect 'nearby' black hole devouring a star
(via sciencedaily.com) Original source Astronomers have discovered a new 'tidal disruption event,' in which the center of a galaxy lights up as its supermassive black hole rips apart a passing star. The outburst is the closest tidal disruption event observed to date, and one of the first to be identified at infrared wavelengths.
Published Superflare with massive, high-velocity prominence eruption
(via sciencedaily.com) Original source A team of Japanese astronomers used simultaneous ground-based and space-based observations to capture a more complete picture of a superflare on a star. The observed flare started with a very massive, high-velocity prominence eruption. These results give us a better idea of how superflares and stellar prominence eruptions occur.
Published Early-nesting ducks at increased risk due to changes in climate, land use
(via sciencedaily.com) Original source Each year approximately 10 million waterfowl fly north to their breeding grounds in the Prairie Pothole Region of North America, but the landscape that greets them has changed. Weather patterns and agricultural practices have significantly transformed the pothole-dotted native grasslands that waterfowl have used for thousands of years.
Published Most massive touching stars ever found will eventually collide as black holes
(via sciencedaily.com) Original source A new study looked at a known binary star (two stars orbiting around a mutual center of gravity), analyzing starlight obtained from a range of ground- and space-based telescopes. The researchers found that the stars, located in a neighboring dwarf galaxy called the Small Magellanic Cloud, are in partial contact and swapping material with each other, with one star currently 'feeding' off the other. They orbit each other every three days and are the most massive touching stars (known as contact binaries) yet observed.
Published Direct image of a black hole expelling a powerful jet
(via sciencedaily.com) Original source Astronomers have observed, in one image, the shadow of the black hole at the center of the galaxy Messier 87 (M87) and the powerful jet expelled from it. Thanks to this new image, astronomers can better understand how black holes can launch such energetic jets.
Published How the Amazon rainforest is likely to cope with the effect of future drought
(via sciencedaily.com) Original source A major collaboration involving 80 scientists from Europe and South America has identified the regions of the Amazon rainforest where trees are most likely to face the greatest risk from drier conditions brought about by climate change. Based on the analysis, the scientists predict trees in the western and southern Amazon face the greatest risk of dying. They also warn that previous scientific investigations may have underestimated the impact of drought on the rainforest because those studies focused on the central-eastern part of the forest, which is the least vulnerable to drought.
Published A healthy but depleted herd: Predators decrease prey disease levels but also population size
(via sciencedaily.com) Original source Nature documentaries will tell you that lions, cheetahs, wolves and other top predators target the weakest or slowest animals and that this culling benefits prey herds, whether it's antelope in Africa or elk in Wyoming. This idea has been widely accepted by biologists for many years and was formalized in 2003 as the healthy herds hypothesis. It proposes that predators can help prey populations by picking off the sick and injured and leaving healthy, strong animals to reproduce.
Published Astronomers solve the 60-year mystery of quasars -- the most powerful objects in the Universe
(via sciencedaily.com) Original source Scientists have unlocked one of the biggest mysteries of quasars -- the brightest, most powerful objects in the Universe -- by discovering that they are ignited by galaxies colliding.
Published Medium-sized black holes eat stars like messy toddlers
(via sciencedaily.com) Original source In new 3D computer simulations, astrophysicists modeled black holes of varying masses and then hurled stars (about the size of our sun) past them to see what might happen. If they exist, intermediate-mass black holes likely devour wayward stars like a messy toddler -- taking a few bites and then flinging the remains across the galaxy.
Published Mixing theory, observation to envision warmer world
(via sciencedaily.com) Original source A more realistic look at what a hot summer can bring to a nearby pond, and new respect for the blinding speed global warming is bringing.
Published Astrophysicists reveal the nature of dark matter through the study of crinkles in spacetime
(via sciencedaily.com) Original source Astrophysicists have provided the most direct evidence yet that Dark Matter does not constitute ultramassive particles as is commonly thought but instead comprises particles so light that they travel through space like waves. Their work resolves an outstanding problem in astrophysics first raised two decades ago: why do models that adopt ultramassive Dark Matter particles fail to correctly predict the observed positions and the brightness of multiple images of the same galaxy created by gravitational lensing?
Published Mysterious underwater acoustic world of British ponds revealed in new study
(via sciencedaily.com) Original source The previously hidden and diverse underwater acoustic world in British ponds has been uncovered by a team of researchers.
Published Asteroid's comet-like tail Is not made of dust, solar observatories reveal
(via sciencedaily.com) Original source We have known for a while that asteroid 3200 Phaethon acts like a comet. It brightens and forms a tail when it's near the Sun, and it is the source of the annual Geminid meteor shower, even though comets are responsible for most meteor showers. Scientists had blamed Phaethon's comet-like behavior on dust escaping from the asteroid as it's scorched by the Sun. However, a new study using two NASA solar observatories reveals that Phaethon's tail is not dusty at all but is actually made of sodium gas.